1. Field of the Invention
The present invention relates to a treatment instrument for endoscope and a lymph node removing method, and in particular to a treatment instrument for endoscope suitable for removing a lymph node and a lymph node removing method of removing a lymph node with the use of the treatment instrument for endoscope which protrudes from the distal end portion of an endoscope inserted in an esophagus or a trachea.
2. Description of the Related Art
In a case of lung cancer, diagnosis of non-small cell lung cancer (NSCLC), that is, diagnosis of cancer metastasis to a lymph node is an important prognostic factor. Especially judgment on whether cancer metastasis is recognized on a mediastinal lymph node and a hilum of lung (hereinafter, these are also referred to simply as “lymph nodes”) is important in considering operability, preoperative and postoperative treatment, and prognosis.
FIG. 1 is a diagram for illustrating the positions of mediastinal lymph nodes and hilar lymph nodes. As shown in FIG. 1, these lymph nodes are scattered around a trachea 4 and an esophagus 5. In order to check cancer metastasis to each lymph node 2, it is strongly desired to remove and examine a tissue of the lymph node 2.
As a lymph node removing method, a method using a mediastinoscope is performed. In the method using a mediastinoscope, an operator cuts the skin at the bottom of a patient's neck and pushes open the tissue at the front part of the trachea to make a space and insert the mediastinoscope. Then, the operator removes the lymph node 2 around the trachea 4 or the esophagus 5 while looking at an endoscopic image.